airbag systems work on a resistance measurement of the ABS loom, so if there is an issue an error is thrown up. normally a bad connection. Worn clock springs have been known to be an issue for jeeps which the airbag uses for it's power. Just by disconnecting a connection can throw up errors. As Mike suggests scanning the system for the error codes will help plus you should be able to clear the error. Remember ECU scanners give you an idea where the problem might be and not a 100% solution